Ventilation valve



FIG. 1 is a front view of first embodiment of a ventilation valve showing our new design;

FIG. 2 is a top front perspective view thereof;

FIG. 3 is a bottom perspective view thereof;

FIG. 4 is a top plan view thereof;

FIG. 5 is a front perspective view of the second embodiment of a ventilation valve showing our new design;

FIG. 6 is a front view thereof;

FIG. 7 is a bottom perspective view thereof; and,

FIG. 8 is a top plan view thereof. 

CLAIM The ornamental design for a ventilation valve, as shown and described. 